4pPPa6. Uni- and multidimensional identification of rise time, spectral
slope, and bandwidth.

A series of experiments was used to evaluate absolute identification
resolution for rise time, bandwidth, and spectral slope. Stimuli were complex
tones comprising the first 40 harmonics of 200 Hz. Ranges for each physical
dimension were restricted to those with validity to natural music and speech
signals, and the number of categories ranged from three to five. A paradigm
similar to one designed to assess channel capacity, perceptual interaction, and
the relationship between uni- and multidimensional resolution [Durlach et al.,
Percept. Psychophys. 46, 293--296 (1989)] was employed. Performance was
quantified in terms of information transfer. Unidimensional identifications
were made for both fixed and roved background conditions in order to determine
the extent to which the dimensions interacted perceptually. Resolution in two-
and three-dimensional identification tasks were compared to resolution in
unidimensional tasks in order to assess the degree to which the summed
unidimensional information transfers from both fixed and roved background
conditions predict multidimensional information transfer. [Work supported by
the Virginia Merrill Bloedel Hearing Research Center.]